1. Technical Field
The present invention relates to a facsimile apparatus, an optional unit, and a control system of optional units.
2. Related Art
A configuration of a main body of a multifunctional machine or the like provided with a facsimile function, a copy function, and a print function, for example, to which a user can arbitrarily add sheet supply cassettes (sheet supply units) as optional units, is known. To such sheet supply units, a drive voltage is supplied from the side of the main body. However, if an inrush current is generated in the respective optional units at the same timing as when power supply is started, a value of a current output from the side of the main body temporarily becomes excessively large due to a total inrush current, and a large burden is applied to the side of the main body.
A configuration in which switches and timing generation circuits with different time constants are provided in an IP telephone terminal and the respective optional units and timings at which drive power is supplied to load circuits in the respective units are differentiated between the IP telephone terminal and the respective optional units when power supply is started is disclosed (see JP-A-2006-19986).
In order to differentiate the timings at which the drive power is supplied to the load circuits in the respective units as disclosed in JP-A-2006-19986, it is necessary to provide timing generation circuits with different time constants in the respective optional units. For this reason, it is not possible to respond to a requirement for mass producing optional units of the same specification to an extent necessary for enhancing production efficiency.
Although a configuration is also considered in which variable resistors are provided in the timing generation circuits to allow a user to set different time constants for the respective optional units, it is necessary for the user to perform complicated operations, and there is also a possibility that erroneous setting may be performed.